Method for manufacturing master of die for shaping golf ball
CA 2097451 C · Owner: Sumitomo Rubber Industries, Ltd. · Inventors: Banji, Masatoshi
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A method for forming a plurality of small concavities for forming dimples on the surface of the golf ball on the, hemispherical surface of the material of a master by electric discharge machining, is carried out in such a manner that the concavities are nonspherical in the direction perpendicular to the hemispherical surface and in a vertical section through each concavity.
Read the whole patent
Listed from its CIPO record in Patent Yard's archive of Canadian patents past their term. Its claims, description and drawings are in the CIPO record and on Google Patents, and the Claude kit works from them.
Why it's free to use
- Filed June 1, 1993 and granted January 26, 1999. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended June 1, 2013.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by June 1, 2015.
- We check Canadian rights only. A patent in its family in another country could still be in force: check its family on Google Patents.
Timeline
Timeline From CIPO dates
Sources & verification
Official CIPO records
Everything on this page comes from the CIPO record linked above. Contains information licensed under the Open Government Licence – Canada.